Merge branch 'stable-3.1' * stable-3.1: Upgrade bazlets to latest stable-3.1 to build with 3.1.6 API Upgrade bazlets to latest stable-3.0 to build with 3.0.10 API Upgrade bazlets to latest stable-2.16 to build with 2.16.21 API Upgrade bazlets to latest stable-2.15 to build with 2.15.19 API Upgrade bazlets to latest stable-2.14 to build with 2.14.21 API Change-Id: I56c1895214f0f459679f8842bfb2e11f253ec85d